For most of the 42.195km race, Singapore's top marathoner Mok Ying Ren led the pack of Singapore men, with runners Soon Suan Boon and Alex Ong keeping pace.

So imagine their surprise when they heard the name Tam Chua Puh being bandied about as the winner of the local men's category at the Standard Chartered Marathon Singapore.

"I had never heard of him before," said the 27-year-old Soon, a regular on the local running circuit for over seven years. "I don't even know what he looks like."

Even more astonishing was that Tam was said to have crossed the finishing line in 2hr 46min 57sec - some seven minutes ahead of Mok.

The mystery deepened when, after a two-hour delay, Mok was announced as the winner of the category.

Event organiser Spectrum Worldwide yesterday confirmed that Tam had been disqualified after investigations were carried out and "revealed discrepancies with his various split times".

"Tam did not launch an appeal following the disqualification and Mok was subsequently confirmed as the official winner of the category," a spokesman for Spectrum told The Straits Times.

According to official results, Tam was also disqualified in the 2011 Singapore marathon, when he ran in the 40-49 age group.

Attempts to contact him through his mobile phone and e-mail have been unsuccessful.

According to the event's live tracking service, he took 58:46 to reach the 5km mark - the only checkpoint he registered at.

Based on the time at which he crossed the finishing line, he would have completed the remaining 37.195km in 1:48:11, or at a pace of 2:55 per kilometre.

To put that figure into perspective, Kenya's Luka Chelimo Kipkemboi won the Men's Open race with an average split of 3:12.

"It's definitely not possible," Ivan Low, who has been competing regularly in distance running events since 2011, said of Tam's supposed feat.

Soon, one of several seasoned local participants who ran most of the race alongside Mok, agreed.

"The first few Singaporeans were running in a close pack," recalled the third local finisher.

"We were all sure that Mok was the first to come in.

"At no point of the race was Tam on our radar."

FABIUS CHEN